1. Field of the Invention
The invention is directed to a rotor of a turbomachine.
2. Detailed Description of Related Art
A rotor of a turbomachine, particularly of a gas turbine or steam turbine, has a main rotor body and a plurality of rotor blades which are fastened to the main rotor body. The rotor blades of a turbomachine rotor of this kind have a blade root and a blade body. Every rotor blade is fastened by its blade root to the main rotor body, and every rotor blade has in the region of its blade body at least one coupling element segment constructed as an outer shroud segment when this coupling element segment is positioned on the radially outer side of the blade body. The coupling element segments, particularly the outer shroud segments, of all of the rotor blades of a turbomachine rotor of this kind form at least one circumferentially closed coupling element, particularly an outer shroud, of the rotor.
Considered in circumferential direction of a turbomachine rotor, a width of a coupling element segment, particularly of an outer shroud segment, of every rotor blade is defined by edges extending substantially in axial direction. A depth in axial direction of the coupling element segment, particularly of the outer shroud segment, of every rotor blade is defined by edges extending substantially in circumferential direction. Aside from the width in circumferential direction and the depth in axial direction, a coupling element segment, particularly an outer shroud segment, of every rotor blade is also characterized by a thickness in radial direction.
Turbomachine rotors whose rotor blades have coupling element segments of the type mentioned above for forming at least one coupling element can be installed in the region of the compressor as well as in the region of a turbine of the turbomachine.
Turbomachine rotors having rotor blades that are fastened to their main rotor body and that have, at the radially outer side of the blade body, a coupling element segment formed as an outer shroud segment are known, for example, from DE 1 159 965 C, DE 40 15 206 C1, U.S. Pat. No. 4,400,915 A, and GB 2 072 760 A.
The coupling elements of turbomachine rotors of the type mentioned above formed as outer shrouds are particularly exposed to high loads in operation because they rotate at maximum radius with respect to an axis of rotation of the turbomachine rotor and are therefore subject to high centrifugal forces. As a result of the centrifugal load, corners and edges of the coupling element segments of the rotor blades can bend outward so that on the one hand stress peaks are caused in the coupling element and on the other hand a desirable contact between adjacent coupling element segments of adjacent rotor blades is reduced to punctiform contact or disappears entirely, which reduces or eliminates a desired coupling between adjacent coupling element segments so that the vibration behavior of the turbomachine rotor eventually deteriorates.